7-Hydroxy-4-trifluoromethylcoumarin , its cas register number is 575-03-1. It also can be called 7,4-Hfc ; 2H-1-Benzopyran-2-one, 7-hydroxy-4-(trifluoromethyl)- .It is a off-white to light yellow or pink powder.
Usage:
Suitable as pH-indicator. Trifluoromethylumbelliferone is a slightly longer wavelength analog of 4-methylcoumarin (4-MU) with a pKa that more closely matches physiological pH values.